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Steel 4012-A vs 4012-HR

Steel · 4012 temper comparison

4012-A and 4012-HR are two conditions of the same steel grade, 4012: A (solution annealed) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. 4012-HR is the stronger of the two: yield strength 320 MPa (46.4 ksi) against 295 MPa (42.8 ksi) for 4012-A, about 8% more; tensile strength follows at 480 MPa (69.6 ksi) vs 440 MPa (63.8 ksi). In exchange, 4012-A is the more ductile: elongation 32% versus 27% for 4012-HR, and 4012-HR is harder (143 HB vs 126 HB).

4012-AChoose it when the part is bent, formed or impact-loaded.

4012-HRChoose it when strength drives the design.

4012-A vs 4012-HR: properties

4012-A4012-HR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

440 MPa63.8 ksi
480 MPa69.6 ksi

Yield Strength (0.2% offset)

295 MPa42.8 ksi
320 MPa46.4 ksi

Elongation at Break

32%
27%

Reduction in Area

65%
55%

Shear Strength

330 MPa47.9 ksi
320 MPa46.4 ksi

Fatigue Strength (Endurance Limit)

205 MPa29.7 ksi
220 MPa31.9 ksi

Charpy V-Notch Impact (RT)

100 J73.8 ft·lbf
85 J62.7 ft·lbf

Hardness, Brinell

126 HB
143 HB

Hardness, Rockwell B

71 HRB
78 HRB

Hardness, Vickers

132 HV
150 HV

Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,510°C2,750 °F

Thermal

How each material carries heat and how hot it can run.

Same in both: Thermal Conductivity 44 W/m·K25.4 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.2 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 7.8 % IACS · Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

12 / 100
11 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

60 / 100
55 / 100

Machinability Rating (AISI 1212 = 100 %)

68%
60%

Weldability

82 / 100
80 / 100

Formability (cold)

78 / 100
68 / 100

Same in both: Brazeability / Solderability 70 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 29 MJ/kg12,468 BTU/lb · Embodied Carbon (primary production) 2.1 kg CO₂/kg · Embodied Water 60 L/kg7.2 gal/lb · Typical Recycled Content 30%

Strength versus weight

Yield strength against density for every steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scale4012

4012-A vs 4012-HR — frequently asked

Is 4012-HR stronger than 4012-A?

Yes. 4012-HR has a typical yield strength of 320 MPa (46.4 ksi) against 295 MPa (42.8 ksi) for 4012-A — about 8% more. Tensile strength is 480 MPa (69.6 ksi) vs 440 MPa (63.8 ksi).

Which condition does FabDigit quote by default, A or HR?

N is the default 4012 condition in the FabDigit quote flow (neither A nor HR). The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.

Which is easier to machine, 4012-A or 4012-HR?

4012-A, by a small margin. Both rate good for machinability — 60/100 against 55/100 for 4012-HR.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 4012-A and 4012-HR side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.

Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.